Random String Generator

What the character list contains

The letter and digit list is abcdefghijklmnopqrstuvwxyz, then ABCDEFGHIJKLMNOPQRSTUVWXYZ, then 0123456789. That is 62 characters. Include symbols appends !@#$%^&*()-_=+[]{}<>? and nothing else. That symbol list is 21 characters, so the checked box uses 83 characters. There is no second box for uppercase alone, lowercase alone, or digits alone. Clearing Include symbols removes the whole symbol list. It does not remove letters that look like digits.

The password generator is a different alphabet and a different shape. Its symbol list adds a vertical bar, a semicolon, a colon, a comma, and a period that this page never uses, it can drop 0, O, 1, l, and I, and it can print up to 50 lines. This page prints one line and cannot drop look-alike characters. A custom alphabet, the kind the NanoID generator offers, is not a control here. If the token must be a UUID, use the UUID generator. The characters in this result are not grouped with hyphens.

Length, the checkbox, and Generate

Length is a number input labeled Length, with min 4 and max 256. Typing 3 becomes 4. Typing 300 becomes 256. Clearing the box becomes 4, because a non-numeric value is treated as 4 before the clamp. Generate repeats that clamp and writes the clamped number back into the box, so a draw never uses a length outside 4 to 256. The default before you edit is 24.

Include symbols is a checkbox. Changing it does not draw a new string by itself. The previous Random output stays until Generate runs with the alphabet you just chose. Generate builds a 32-bit buffer with one entry per character, fills it with crypto.getRandomValues, and picks chars[value % chars.length] for each entry. With 83 symbols-and-letters, that remainder is not a perfectly even split of the 32-bit range. The page does not reject a biased draw and it does not offer a different sampler.

Jobs for one random string

Use it when a form, a fixture, or a log line needs one opaque token and you want to choose 8 characters or 64. Leave the symbols on when the consumer accepts them. Turn them off when the consumer is a code that only allows letters and digits, because a # or a bracket will otherwise show up. The result is one row. If you need several independent strings, press Generate, copy, and press Generate again. The page will not stack them.

A whole number in a range is the random number generator, which can print up to 500 integers and does not print letters. A password that must mix character classes and hide ambiguous glyphs is the password page, not this one. Nothing here estimates a collision time, and nothing here checks the string against a breach list.

What is restored, and what is not

Length, the symbols checkbox, and the last string are written to local storage in this browser under the key for this tool. A later visit restores them after the page hydrates. Generate is what changes the string. Reloading does not draw a new one. Clearing site data for the browser drops that saved triple. The page has no Clear button of its own.

Before the first successful Generate in a fresh browser, Random output is empty and Copy output reports that there is nothing to copy. After a draw, Copy output copies that one string with no label and no trailing newline added by the tool. The length you see in the box is the length of the string. Symbols are mixed through the same remainder pick as the letters. They are not guaranteed to appear in a short string even when the box is checked, because each position is an independent pick from the full 83.

Rules and limitations

One string per Generate click. Length is an integer from 4 to 256, default 24. The base alphabet is 52 letters and 10 digits. Include symbols adds the 21 characters !@#$%^&*()-_=+[]{}<>?.

Each character is crypto.getRandomValues modulo the alphabet length. There is no bulk count, no custom alphabet, no ambiguous-character filter, and no download. Length, the checkbox, and the last string are restored from local storage.

Common problems

If the string gained a bracket or a #, Include symbols was checked. Clear it and press Generate. The old string stays on screen until that click.

If the length snapped to 4 or 256, the typed number was outside the clamp. The draw uses the clamped length, not the number you tried to type.

Frequently asked questions

About this tool

Maintained by Toolbench. For large or deeply nested files, split the input into smaller batches and verify representative results before using them in an import or application. Report reproducible problems through Contact.